#include <iostream>
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/time.h>
#include <signal.h>

using namespace std;

void doing(int arg)
{
    cout << "捕捉信号被调用了" << endl;
}
int main(int argc, char **argv)
{

    int a = 0;
    struct itimerval tv = {{2, 0}, {1, 0}};
    setitimer(ITIMER_REAL, &tv, NULL);
    signal(SIGALRM,doing);
    while (1)
    {
       sleep(1);
       ++a;if(a > 10)exit(0);
       cout<< " 循環了 "<< a<< " 次"<< endl;
    }
    

    return 0;
}